1,721,020 research outputs found
Simulating LISP-Based Multilink Communications in Aeronautical Networks
Full text linkOver the next few years, future aeronautical communications are expected to move from the OSI protocol stack to the TCP/IP one. Multiple data-link channels (e.g., satellite, terrestrial) will be available to each aircraft to communicate with ground, realizing the so-called multilink. In order to ensure a seamless handover between different data-links, the LISP protocol has been defined. This paper describes the modelling, design and implementation of LISP on the SAPIENT simulator, an OMNeT++-based simulator for aeronautical communications. It includes models of the aircrafts, including their mobility, multiple data links and ground-network elements
SimuLTE-MEC: extending SimuLTE for Multiaccess Edge Computing
Full text linkMulti-access Edge Computing (MEC) is a novel paradigm to enrich current 4G and future 5G cellular networks by placing cloud-computing-based capabilities at the edge of the network. This will allow operators and service providers to endow the cellular network with enriched services. In this paper we describe the modeling and development of a MEC extension for the SimuLTE framework
Cellular-Networks Simulation Using SimuLTE
No full textThis chapter describes SimuLTE, a framework within the OMNeT++ ecosystem for simulating Long Term Evolution (LTE) networks. The main focus of SimuLTE lies on developing and testing of communication protocols and resource-allocation algorithms, with an emphasis on the impact at the system level. The chapter starts with a detailed description of the SimuLTE architecture, of its main nodes and corresponding protocol layers, and of the main functions. Then two tutorials on the modeling and performance evaluation of two LTE-related research problems are presented, namely, one concerning interference coordination and one on direct-communication management. Each tutorial provides guidelines for network definition, for configuring the scenario, and their parameters. The tutorials also describe how to modify the code of the available functions. Exemplary result analysis is presented along with each tutorial, to demonstrate the evaluation capabilities of the framework
Simulating LTE-Enabled Vehicular Communications
No full textIn the next years, cellular networks are expected to foster the development of inter-vehicle communication supporting advanced driver-assistance systems and self-driving cars. The evaluation of such systems can be performed via OMNeT++, which supports two independent frameworks for simulating Vehicle-to-Everything (V2X) communications and Long Term Evolution (LTE) technology, i.e., Artery and SimuLTE. The aim of this chapter is to combine Artery and SimuLTE in order to simulate V2X services relying on cellular communications. First, we describe the main challenges that are encountered when integrating the two frameworks. Then, considering the use case of vehicles that need to be warned when approaching a black ice region, we provide two tutorials that describe the configuration of networks and parameters, the implementation of the V2X service, and the collection of simulations results. The first tutorial focuses on vehicles exploiting the cellular infrastructure to communicate with a remote server, to be informed about the danger zone. In the second tutorial, vehicles detecting a traction loss exploit LTE’s Device-to-Device (D2D) capabilities to rapidly distribute the alert to all the vehicles in proximity
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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